Push-on mechanism for sealing screw cap containers under vacuum



March 29, 1949.

BAUMAN 2,465,706

R SEALING SCREW J. 1 PUSH-ON MECHANISM F0 CAP CONTAINERS UNDER VACUUM Filed Nov. 5, 1944 Z/Ij/e/I/a/ @56 7; Baa/M75 Patented Mar. 29, 1949 PUSH-N MECHANISM FOR SEALING SCREW CAP CONTAINERS UNDER VACUUM Joseph Bauman, Wheeling, W. Va., assignor to Hazel-Atlas Glass Company, Wheeling, W. Va., a corporation of West Virginia Application November 3, 1944, Serial No. 561,810

Claims. 1

The invention relates to improvements in apparatus for sealing containers, particularly glass containers, with screw closures, under vacuum, and one of the objects of the invention is to provide means by which screw cap containers can be rapidly and efliciently vacuumized and sealed by less complex mechanism than has heretofore been possible.

Another object of the invention is to provide means whereby an apparatus designed for vacuumizing and sealing containers with push-on caps can be quickly and easily converted into an apparatus for vacuumizing and sealing containers with screw caps.

A further object of the invention is to provide means by which screw caps can be forced downwardly to sealing position, under vacuum, without deforming the cap skirt or threads, whereby the caps may not require retightening, and if they are retightened there will be no leakage of air into the containers during the retightening operation.

Various other objects and advantages of the invention will be apparent to those skilled in the art from the following detailed description, when taken in connection with the accompanying drawings, in which Figure 1 is a vertical sectional view of a closure screwed on the neck of a glass container, but not sealing the container;

Figure 2 is a vertical sectional view of the closure after it has been forced vertically downward to sealing position by a sealing pad construction heretofore known;

Figure 3 is a vertical sectional view of the closure after it has been forced vertically downward to sealing position in accordance with the present invention; and

Figure 4 is a vertical sectional view of a vacuumizer embodying the present invention.

Of course, it is well known to screw caps on containers, by hand or machine, and then vacuumize the containers and, while the containers are under vacuum, screw the caps down to sealing position. But such method of sealing involves rather complex and expensive mechanisms.

When containers are provided with push-on caps, they are sealed under vacuum by merely forcing the caps downwardly to scaling position,

2 without any rotation, and this is done with relatively simple mechanism.

When attempts are made to use the relatively simple vacuumizers for push-on caps for the purpose of forcing screw caps downwardly to sealing position, without rotating the caps, difficulties are encountered which prevent efficient sealing. These difficulties, and the means by which they are overcome by the present invention, will now be described.

Numeral I refers to a glass container which is to be sealed by an ordinary screw cap 2, having a sealing gasket 3. In Figure l the cap is shown as mounted on the container with the threads 4 of the cap engaging the glass threads of the container, but the cap has not been screwed all the way down to sealing position.

The present invention does not relate to means for rotating the screw cap 2 to sealing position under vacuum, but relates to means for forcing the top of the screw cap vertically downward to sealing position, under vacuum.

Figure 2 illustrates the cap 2 after it has been forced down to sealing position by a sealing pad 5 which is of the ordinary construction used in vacuumizers for push-on caps.

These pads 5, of which there may be any desired number in a vacuumizer, and which may be raised and lowered by any desired means, have a horizontal fiat face 8 for engaging the top of caps of the push-on type. This fiat face extends to or beyond the periphery of the cap top.

When such sealing pads are employed to force screw caps down to sealing position, the skirt of the cap containing the threads is forced down and the cap is deformed so that the threads 4 are forced away from the glass threads I, as indicated by numeral 8 in Figure 2.

When the vacuum in the vacuumizer is relieved, the sealing pads lifted, and the containers removed from the vacuumizer, the caps are held in sealing position by atmospheric pressure. But when the caps are now turned to retighten them, the caps immediately change from their deformed shape of Figure 2 to their original shape of Figure 1. This change of shape tends to loosen the cap slightly, thereby permitting the leakage of air into the vacuumized container.

In accordance with the present invention the cap skirt is not deformed and the necessity for retightening is largely eliminated, and if the caps are retightened there is no leakage.

The sealing means of the present invention is illustrated in Figure 3, and instead of the ordinary flat face extending to a point beyond the periphery of the cap, I employ an annular flange or shoulder 9 depending from the sealing pad 10 at a point which is a substantial distance inward of the cap periphery.

Consequently, when the sealing pad I0 is forced downward, only this annular dependingflange engages the cap top andsforces' zthezcap down-.to.

sealing position on the container. But the depending fiange engages the cap top, not at the. v

sealing position, as heretofore described.

periphery, but at a substantial distance inwardly thereof, and consequently thezcapaskirt;iswnot threads ;.are not 4 in Figure 4, a sectional view of a portion of a common and well known vacuumizer for push-on caps. The particular construction illustrated is very similar to the vacuumizer shown and described in the patent to Ingram No. 1,624,869, granted April 12, 1927, and no description thereof is necessary, except to say that the containers with screw caps thereon are placed in the sealing box I2, which is then closed by the door 13. Thereafter the sealing box is vacuumized by means ofapi e l4 leadingto any desired source of-'vacuum,1;an'd then thee-sealing head 15, which has been provided with the novel form of sealing ...pa,ds I0, is lowered to force the screw caps into .ufiaying fullyatdesc'ribed the invention, what I 1. Apparatus for vacuum sealing containers withtopsealscrewcaps engaging threads on the they were, with the cap threads engaging. the,. ,.ccintainers,.including means for Vacuumizing the glass threads, and only the top of the cap,.;.inwardly of its periphery, is forced downwardly to efi'ect the seal, as clearly shown i'n Figure 3.

Also as shown in Figure 3, the face ofcthe an: nular flange or shoulder n9 is preferably inclined slightlyinwardly and downwardly, as indicated by'numeral' I I, but of course the invention is not limitedto any particular-shape.of the cap-tengaging means; the essential feature being that,

containers, avertically reciprocable sealing pad associated with said vacuumizing means, and

- said sea1ing -padshaped to engage the tops of screw :caps beyond the inner circumference of the container neck and only inwardly of the periphery of the caps, whereby thetops of .the screw'caps are forced vertically. downward Ito sealing position without substantially disturbing the relation between .the cap thread. andthe whatever means is employed, it should engage 3Q container thread,

the cap top inwardly. of theperiphery thereof.

From the above description it will be apparent that when a screw cap ishforced 'downwardlyto sealing. position, by the "novel means described,

2.", Apparatus for vacuum sealing containers with top seal screwcaps engaging threads onthe containers, including means for vacuumizing' the containers, avertically reciprocable sealing e C p Skirt andthreads Will 0 b rm d; pad associated with said vacuumizing means,

resulting in the cap threads being forced away from the glass threads. Consequently, when'the vacuum in the vacuumizerisgrelieved, the sealing pads lifted, and the containers removed from the and said sealing pad includingmeans for engag-' ing the tops of screw caps beyond the inner circumference. of" the container neck andon-ly inwardly'of'the periphery of the caps, whereby.

V c y :Will be p op y d, and 40 the tops of the screw .caps arejorced vertically the. caps will be held insealingrelation' by,a,tmospheric pressure and also'by reason of the engagement of the cap threads with-the glass threads.

In such circumstances, any retighteningof the downward tosealing position withoutjsubstantiallyfdisturbing the relation between .the ca'p threa'dgand'the container thread.

"3"..'Al1 aratus"for vacuum sealing containers caps y ro i n may be unnecessary; but if.re-" 4 with top'"seal.,screw-.c.aps engaging threads on the containers; including. means for .vacuumizing.

tightening by rotation shouldbe desirable, it. will be apparent that'there willbeno spoiling ;of .the vacuum by. leakage of airinto. the container, for in the sealing op-erationthe' relation between the cap threads andthe glass threads hasnot been'disturbed, and hence when the cap is retightened pressure onthesealingjmaterial isretained, thereby preventing the seal from :being broken, with the consequent air leakage.

It will also be apparent that any sealingmech'i' all-y "disturbing*the' relation"-between theqcap nis'm designed for-sealing containers with pushon caps, under vacuum, can bequickly converted to use forsealing containers with screw caps,..,by merely substituting for the conventional sealing the containers, a "vertically reciprocable 'sefalin'g pad associated with said vacuumizing means, and said sealing ypa'duncluding depending means for engaging the topskof' screw caps beyond the inner;

thread and the container thread.

4: Apparatus for--vacuum-sealingcontainers with topsealscrew caps eng-aging'threads onthe containers;- including means for vacuumizi-ngthe pads; the novel sealing pads ofthe present. inven.-." Q 9 containers, a vertically reciprocabl'e, non-rotat tion so constructed that the downward pressure willbe exerted inwardlyof the periphery of the caps. Thus the relatively simple vacuumizers for push-on caps are enabled to performthe double function of ,sealing'both push-on. caps and screw caps, and. further, .the ..expens.e...of the relatively complex vacuumizersfor sealing screw cap containers by .the rotation of the screw caps is avoided.

Itwill be understood, of course, that the. inven? tion is in no manner limited to. any; particular form or type of vacuumizer',. for obviously the novel sealing pad can be used in. .any.v,acuum sealing mechanism. Merely. for thepl rposepf. illustration, however," there. is shown generally,

" ing -sealing padassociated with said vacuumizing 9 tion..betw eeri.the..capnthread and the container thread.

5. Apparatus. for ,vacuum t.sealing, ,cpntainers With ta s al sc wca s @nea inathreadscn. the

containers, including.means..for.vacuumizi ng..the 7? containers, ayertically grec iprocable, .nonwrotating sealing pad associated with said vacuumizing means, said sealing pad including a depending REFERENCES CITED flange for engaging the tops of screw caps, the The following references are of record in the exterior diameter of the flange being less than file of this patent:

the diameter of the screw caps engaged and 5 UNITED STATES PATENTS greater than the inner circumference of the container neck, and the lower face of said flange Number Name te being inclined downwardly and inwardly, where- 774,425 Hicks NOV. 8, 904

by the tops of the screw caps are forced vertically 1,624,369 Ingram Ap 2, 7

downward to sealing position without substanti- 10 1,761,433 l une 3, 1930 ally disturbing the relation between the cap 1,355,786 Anderson p 1932 2,106,464 Meyer Jan. 25, 1938 thread and the container thread.

JOSEPH BAUMAN. 

